Basic studies over the past year have shown that high carbohydrate diets suppress growth hormone secretion in men, but not women. Starvation enhances growth hormone secretion more in men than women. We intend to clarify the relationship of these changes to body mass, with emphasis on how the muscle to adipose tissue ratio alters hormonal secretion patterns. Receptor assays for insulin and growth hormone are being developed to study the sensitivity, induceability of receptors, and the factors modifying resistance to hormone action.